Methods to disinfect contact lenses

Abstract

A method for disinfecting a lens is disclosed. The method comprises contacting a lens to be disinfected in a liquid medium with at least one chlorine dioxide precursor in the presence of at least one acidic component effective to increase the rate of formation of chlorine dioxide from the chlorine dioxide precursor, thereby disinfecting the lens; and adjusting the acidity of the liquid medium containing the disinfected lens. Compositions useful in the above-noted method are also disclosed.

What is claimed is: 
     
       1. A method for disinfecting a contact lens which comprises: contacting a contact lens in a first liquid medium with a chlorine dioxide precursor in the presence of an acidic component in an amount to effect formation of a disinfecting amount of chlorine dioxide from said chlorine dioxide precursor, thereby disinfecting said contact lens;   introducing an acidity adjusting component into said first liquid medium, said acidity adjusting component being effective to adjust and control said first liquid medium containing said disinfected contact lens at reduced acidity after being released into said first liquid medium; and   contacting said disinfected contact lens with a second liquid medium having reduced acidity relative to said first liquid medium used in said contact lens contacting.   
     
     
       2. The method of claim 1 wherein each of said first and second liquid media is an aqueous liquid medium. 
     
     
       3. The method of claim 2 wherein said contacting with said first liquid medium occurs at a pH of about 6 or less. 
     
     
       4. The method of claim 3 wherein said second liquid medium has a pH in the range of about 6.5 to about 8. 
     
     
       5. The method of claim 3 wherein said second liquid medium has a pH of about 7.5. 
     
     
       6. The method of claim 2 wherein said contactings occur at a temperature in the range of about 0° C. to about 100° C. 
     
     
       7. The method of claim 2 wherein said contacting in said first liquid medium occurs for a time in the range of about 1 minute to about 12 hours. 
     
     
       8. The method of claim 1 wherein said first liquid medium and said second liquid medium are derived from the same liquid medium. 
     
     
       9. The method of claim 1 wherein said chlorine dioxide precursor is introduced into said first liquid medium as a solid. 
     
     
       10. The method of claim 1 wherein said contacting with said second liquid medium includes at least one of rinsing said disinfected contact lens in a saline solution and soaking said disinfected contact lens in a saline solution. 
     
     
       11. The method of claim 10 wherein said saline solution includes a buffering agent. 
     
     
       12. The method of claim 1 wherein said chlorine dioxide precursor is stabilized chlorine dioxide. 
     
     
       13. The method of claim 1 wherein said chlorine dioxide precursor is selected from the group consisting of chlorine dioxide-containing complexes and mixtures thereof. 
     
     
       14. The method of claim 1 wherein said chlorine dioxide precursor is selected from the group consisting of complexes of chlorine dioxide and carbonate, complexes of chlorine dioxide and bicarbonate, and mixtures thereof. 
     
     
       15. The method of claim 1 wherein said chlorine dioxide precursor is selected from the group consisting of chlorite-containing components and mixtures thereof. 
     
     
       16. The method of claim 1 wherein said chlorine dioxide precursor includes a functionality selected from the group consisting of carbonate, borate, sulfate, phosphate, and mixtures thereof. 
     
     
       17. The method of claim 1 which further comprises introducing an acidic component into said first liquid medium. 
     
     
       18. The method of claim 17 wherein said acidic component is introduced into said first liquid medium as a solid. 
     
     
       19. The method of claim 18 wherein said chlorine dioxide percursor is introduced into said first liquid medium as a solid. 
     
     
       20. The method of claim 19 wherein said chlorine dioxide precursor and said acidic component are introduced into said first liquid medium at substantially the same time. 
     
     
       21. The method of claim 1 wherein said acidic component is selected from the group consisting of mineral acids, carboxylic acids, acidic salts and mixtures thereof. 
     
     
       22. The method of claim 1 wherein said acidic component is selected from the group consisting of carboxylic acids and mixtures thereof. 
     
     
       23. The method of claim 1 wherein said acidic component is selected from the group consisting of alkali metal hydrogen phosphates, citric acid, lactic acid, tartaric acid and mixtures thereof. 
     
     
       24. The method of claim 1 wherein said acidic component is introduced into said first liquid medium in the form of a pill or tablet. 
     
     
       25. The method of claim 1 wherein said acidity adjusting component is introduced into said first liquid medium as a solid. 
     
     
       26. The method of claim 1 wherein said acidity adjusting component is selected from the group consisting of basic components, buffer components and mixtures thereof. 
     
     
       27. The method of claim 1 wherein said acidity adjusting component comprises a mixture of at least one basic component and at least one buffer component. 
     
     
       28. The method of claim 1 wherein said acidic component is introduced into said first liquid medium prior to said acidity adjusting component being introduced into said first liquid medium. 
     
     
       29. The method of claim 1 wherein said acidic component and said acidity adjusting component are introduced into said first liquid medium at substantially the same time. 
     
     
       30. The method of claim 29 wherein said acidic component and said acidity adjusting component are each a part of the same item which is introduced into said first liquid medium. 
     
     
       31. The method of claim 30 wherein said item is structured to release said acidic component prior to releasing said acidity adjusting component. 
     
     
       32. The method of claim 31 wherein said item is structured to release said acidity adjusting component after being introduced into said first liquid medium a sufficient time to provide for the contact lens to be disinfected. 
     
     
       33. The method of claim 1 wherein said second liquid medium includes a reducing agent in an amount effective to chemically reduce at least a portion of the chlorine dioxide formed from said chlorine dioxide precursor. 
     
     
       34. The method of claim 1 which further comprises introducing a reducing agent effective to chemically reduce at least a portion of the chlorine dioxide formed from said chlorine dioxide precursor into said first liquid medium. 
     
     
       35. The method of claim 34 wherein said acidity adjusting agent and said reducing agent are introduced into said first liquid medium at substantially the same time. 
     
     
       36. The method of claim 1 which further comprises contacting the contact lens in a liquid medium with at least one enzyme capable of removing debris from a contact lens in an amount effective to remove debris from the contact lens. 
     
     
       37. The method of claim 36 wherein the contact lens is contacted with said at least one enzyme prior to said contacting with said chlorine dioxide precursor. 
     
     
       38. The method of claim 37 wherein said liquid medium is said first liquid medium. 
     
     
       39. The method of claim 38 wherein said at least one enzyme and said acidic component are introduced into said first liquid medium at substantially the same time. 
     
     
       40. The method of claim 39 wherein said at least one enzyme and said acidic component are each part of the same item introduced into said first liquid medium. 
     
     
       41. The method of claim 40 wherein said item is structured to release said at least one enzyme prior to releasing said acidic component. 
     
     
       42. The method of claim 38 wherein the contact lens is contacted with said at least one enzyme after being disinfected. 
     
     
       43. The method of claim 42 wherein said liquid medium is said first liquid medium. 
     
     
       44. The method of claim 43 which further comprises introducing a reducing agent effective to chemically reduce at least a portion of the chlorine dioxide formed from said chlorine dioxide precursor into said first liquid medium. 
     
     
       45. The method of claim 36 wherein said at least one enzyme is selected from the group consisting of proteolytic enzymes, lipases and mixtures thereof. 
     
     
       46. The method of claim 36 wherein said at least one enzyme is selected from the group consisting of carbohydrate active enzymes and mixtures thereof. 
     
     
       47. The method of claim 36 wherein said at least one enzyme is selected from the group consisting of proteases, amylases, lipases and mixtures thereof. 
     
     
       48. The method of claim 38 wherein said at least one enzyme and said acidity adjusting component are introduced into said first liquid medium at substantially the same time. 
     
     
       49. The method of claim 48 wherein said at least one enzyme and said acidity adjusting component are each part of the same item introduced into said first liquid medium. 
     
     
       50. The method of claim 49 wherein said same item is structured to release said acidity adjusting component prior to releasing said at least one enzyme or at substantially the same time as said at least one enzyme is released. 
     
     
       51. The method of claim 49 wherein said same item further includes a reducing agent effective to chemically reduce at least a portion of the chlorine dioxide formed from said chlorine dioxide precursor. 
     
     
       52. The method of claim 51 wherein said same item is structured to release said acidity adjusting component and said reducing agent prior to releasing said at least one enzyme or at substantially the same time as said at least one enzyme is released. 
     
     
       53. A method for disinfecting a contact lens which comprises: (1) contacting a contact lens in a first liquid medium with a chlorine dioxide precursor in the presence of an acidic component in an amount to effect formation of a disinfecting amount of chlorine dioxide from said chlorine dioxide precursor, thereby disinfecting said contact lens; and   (2) contacting said disinfected contact lens in a second liquid medium derived from said first liquid medium and having an acidity at the conclusion of step (2) which is reduced relative to said first liquid medium used in step (1).   
     
     
       54. The method of claim 53 wherein each of said first and second liquid media in an aqueous liquid medium. 
     
     
       55. The method of claim 54 wherein said contacting with said first liquid medium occurs at a pH of about 6 or less, and said second liquid medium has a pH in the range of about 6.5 to about 8. 
     
     
       56. The method of claim 53 wherein said chlorine dioxide precursor is introduced into said first liquid medium as a solid. 
     
     
       57. The method of claim 53 wherein said chlorine dioxide precursor is stabilized chlorine dioxide. 
     
     
       58. The method of claim 53 which further comprises introducing said acidic component into said first liquid medium. 
     
     
       59. The method of claim 53 wherein said acidic component is selected from the group consisting of mineral acids, carboxylic acids, acidic salts and mixtures thereof. 
     
     
       60. The method of claim 53 wherein said second liquid medium includes a reducing aent in an amount effective to chemically reduce at least a portion of the clorine dioxide formed from said chlorine dioxide precursor. 
     
     
       61. The method of claim 53 which further comprises introducing a reducing agent effective to chemically reduce at least a portion of the chlorine dioxide formed from said chlorine dioxide precursor into said first liquid medium. 
     
     
       62. The method of claim 53 which further comprises contacting the contact lens in a liquid medium with at least one enzyme capable of removing debris from a contact lens in an amount effective to remove debris from the contact lens. 
     
     
       63. The method of claim 62 wherein the contact lens is contacted with said at least one enzyme prior to step (1). 
     
     
       64. The method of claim 63 wherein said liquid medium is said first liquid medium. 
     
     
       65. The method of claim 64 wherein said enzyme and said at least one acidic component are introduced into said first liquid medium at substantially the same time. 
     
     
       66. The method of claim 62 which further comprises introducing an acidity adjusting component into said first liquid medium. 
     
     
       67. The method of claim 66 wherein said at least one enzyme and said acidity adjusting component are introduced into said first liquid medium at substantially the same time. 
     
     
       68. The method of claim 67 wherein said at least one enzyme and said acidity adjusting component are each part of the same item introduced into said first liquid medium. 
     
     
       69. The method of claim 68 wherein said same item is structured to release said acidity adjusting component prior to releasing said at least one enzyme or at substantially the same time as said at least one enzyme is released. 
     
     
       70. A method for disinfecting a contact lens which comprises: (1) contacting a contact lens in a first liquid medium with a chlorine dioxide precursor in the presence of an acidic component in an amount to effect formation of a disinfecting amount of chlorine dioxide from said chlorine dioxide precursor, thereby disinfecting said contact lens; and   (2) contacting said disinfected contact lens with a second liquid medium having an acidity at the conclusion of step (2) which is reduced relative to said first liquid medium used in step (1), said second liquid medium including at least one reducing agent in an amount effective to chemically reduce at least a portion of the chlorine dioxide formed from said chlorine dioxide precursor.   
     
     
       71. The method of claim 70 wherein each of said first and second liquid media is an aqueous liquid medium. 
     
     
       72. The method of claim 71 wherein said contacting with said first liquid medium occurs at a pH of about 6 or less, and said second liquid medium has a pH in the range of about 6.5 to about 8. 
     
     
       73. The method of claim 70 wherein said chlorine dioxide precursor is stabilized chlorine dioxide. 
     
     
       74. The method of claim 70 which further comprises introducing said reducing agent into said first liquid medium.